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        <td class="header">&nbsp;&nbsp;<b><span style="font-size: 14pt; line-height: 115%;" lang="EN">Multi-Pol
Pre-Processing</span></b>
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<p class="MsoNormal" style=""><span style="" lang="EN"></span>Multi-Pol
    pre-processing takes a single C-band Quad Pol SLC
    product as input.&nbsp;
</p>
<p class="MsoNormal" style="">The processing graph
    applies:</p>
<ul>
    <li>Radiometric calibration to Sigma0</li>
    <li>Mean 3x3 speckle filtering</li>
    <li>Terrain correction using the SRTM 3sec DEM and map
        projection to WGS84 Lat/Lng geographic coordinates
    </li>
</ul>
<p>The
    multi-angle soil moisture retrieval requires that the terrain
    correction operator output the incidence angle from the ellipsoid as a
    band.</p>

<p></p>

<p>Pre-processing
    could also be applied from outside the Toolbox. In this case, the input
    product must adhere to the following input product conditions:</p>
<ol>
    <li>The input product must be calibrated to Sigma0</li>
    <li>All
        required source bands, namely, sigma0HH, sigma0VV
        and&nbsp;Incidence
        Angle&nbsp;must be present in a single input source product.
    </li>
    <li>The
        sigma0HH band name should contain "Sigma0_HH" or "HH" with "Sigma0_HH"
        taking precedence meaning that if a band whose name contains
        "Sigma0_HH" is found, other bands whose name contains "HH" will be
        ignored.
    </li>
    <li>The sigma0VV band name should contain "Sigma0_VV" or "VV"
        with "Sigma0_VV" taking precedence.
    </li>
    <li>If no unit is specified for the sigma0 bands or the unit is
        not decibel (dB), the sigma0 values will be converted to dB.
    </li>
    <li>The
        incidence angle band could be local incidence angle (LIA) or incidence
        angles from the ellipsoid. Incidence angles should be in degrees.
    </li>
    <li>The incidence angle band name should contain
        "incidenceAngle" or "LIA" with "incidenceAngle" taking precedence.<br>
        <br>
    </li>
</ol>
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